Files
Archive/netch/Redirector/DNSHandler.cpp
2024-03-05 02:32:38 -08:00

129 lines
3.3 KiB
C++

#include "DNSHandler.h"
#include "SocksHelper.h"
extern bool dnsProx;
extern string dnsHost;
extern USHORT dnsPort;
SOCKADDR_IN6 dnsAddr;
void HandleClientDNS(ENDPOINT_ID id, PSOCKADDR_IN6 target, char* packet, int length, PNF_UDP_OPTIONS option)
{
auto remote = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
if (remote != INVALID_SOCKET)
{
int v6only = 0;
if (setsockopt(remote, IPPROTO_IPV6, IPV6_V6ONLY, (char*)&v6only, sizeof(v6only)) != SOCKET_ERROR)
{
SOCKADDR_IN6 addr;
IN6ADDR_SETANY(&addr);
if (bind(remote, (PSOCKADDR)&addr, sizeof(SOCKADDR_IN6)) != SOCKET_ERROR)
{
if (sendto(remote, packet, length, 0, (PSOCKADDR)&dnsAddr, (dnsAddr.sin6_family == AF_INET ? sizeof(SOCKADDR_IN) : sizeof(SOCKADDR_IN6))) == length)
{
timeval timeout{};
timeout.tv_sec = 4;
fd_set fds;
FD_ZERO(&fds);
FD_SET(remote, &fds);
int size = select(NULL, &fds, NULL, NULL, &timeout);
if (size != 0 && size != SOCKET_ERROR)
{
char buffer[1024];
size = recvfrom(remote, buffer, sizeof(buffer), 0, NULL, NULL);
if (size != 0 && size != SOCKET_ERROR)
nf_udpPostReceive(id, (PBYTE)target, buffer, size, option);
}
}
}
}
}
if (remote != INVALID_SOCKET)
closesocket(remote);
delete target;
delete[] packet;
delete[] option;
}
void HandleRemoteDNS(ENDPOINT_ID id, PSOCKADDR_IN6 target, char* packet, int length, PNF_UDP_OPTIONS option)
{
auto remote = new SocksHelper::UDP();
if (remote->Associate())
{
if (remote->CreateUDP())
{
if (remote->Send(&dnsAddr, packet, length) == length)
{
char buffer[1024];
timeval timeout{};
timeout.tv_sec = 4;
int size = remote->Read(NULL, buffer, sizeof(buffer), &timeout);
if (size != 0 && size != SOCKET_ERROR)
nf_udpPostReceive(id, (PBYTE)target, buffer, size, option);
}
}
}
delete remote;
delete target;
delete[] packet;
delete[] option;
}
bool DNSHandler::INIT()
{
memset(&dnsAddr, 0, sizeof(dnsAddr));
auto ipv4 = (PSOCKADDR_IN)&dnsAddr;
if (inet_pton(AF_INET, dnsHost.c_str(), &ipv4->sin_addr) == 1)
{
ipv4->sin_family = AF_INET;
ipv4->sin_port = htons(dnsPort);
return true;
}
auto ipv6 = (PSOCKADDR_IN6)&dnsAddr;
if (inet_pton(AF_INET6, dnsHost.c_str(), &ipv6->sin6_addr) == 1)
{
ipv6->sin6_family = AF_INET6;
ipv6->sin6_port = htons(dnsPort);
return true;
}
return false;
}
bool DNSHandler::IsDNS(PSOCKADDR_IN6 target)
{
if (target->sin6_family == AF_INET)
return ((PSOCKADDR_IN)target)->sin_port == htons(53);
else
return target->sin6_port == htons(53);
}
void DNSHandler::CreateHandler(ENDPOINT_ID id, PSOCKADDR_IN6 target, const char* packet, int length, PNF_UDP_OPTIONS options)
{
auto remote = new SOCKADDR_IN6();
auto buffer = new char[length]();
auto option = (PNF_UDP_OPTIONS)new char[sizeof(NF_UDP_OPTIONS) + options->optionsLength];
memcpy(remote, target, sizeof(SOCKADDR_IN6));
memcpy(buffer, packet, length);
memcpy(option, options, sizeof(NF_UDP_OPTIONS) + options->optionsLength - 1);
if (!dnsProx)
thread(HandleClientDNS, id, remote, buffer, length, option).detach();
else
thread(HandleRemoteDNS, id, remote, buffer, length, option).detach();
}